Science

Can 'Rewilding' Restore Vanishing Ecosystems?

Wolves were native to the Yellowstone National Park until hunting wiped them out. In 1995, when the wolves began to come back, something interesting happened: The rest of the park began to find a new, more healthful balance.

About George Monbiot

Journalist George Monbiot is author of the book Feral: Rewilding the Land, the Sea, and Human Life. The book follows Monbiot's efforts to re-engage with nature. He shows how, by restoring and rewilding our damaged ecosystems on land and at sea, we can bring wonder back into our lives, and lays out a new, positive environmental vision, in which nature is allowed to find its own way.

It's the TED Radio Hour from NPR. I'm Guy Raz. And today's show is about how everything is connected, how teeny tiny, almost imperceptible changes to our natural world can have a profound impact on everything within it, even us. And today, we're going to hear from TED speakers who will explain why every flower, every insect, every animal, even every sound has a very specific, very crucial role in keeping it all in balance.

(SOUNDBITE OF WOLF HOWL)

RAZ: We're going to start with a story about wolves, which is the sound we're all enjoying at the moment. Anyway, a few years ago, the British writer and environmentalist George Monbiot got really into them, into wolves, and it happened in the middle of a midlife crisis.

GEORGE MONBIOT: I'd like to point out that I didn't buy a motorbike. I bought a sea kayak.

RAZ: This is George.

MONBIOT: I found myself as I got older, just scratching at the walls of it, not feeling that I was sufficiently exercised. That I had so many faculties which weren't being used.

(SOUNDBITE OF TED TALK)

MONBIOT: I was, I believe, ecologically bored.

RAZ: This is the opening from his TED Talk.

(SOUNDBITE OF TED TALK)

MONBIOT: And it was only when I stumbled across an unfamiliar word, that I began to understand what I was looking for. And as soon as I found that word, I realized that I wanted to devote much of the rest of my life to it. The word is rewilding.

(SOUNDBITE OF WOLF HOWLING)

RAZ: So this is where the wolves come in because at the time, George wanted to figure out why so many gray wolves had been hunted and killed to near-extinction in North America. And how we turned them into these terrifying monsters.

MONBIOT: That's why there's all these stories about werewolves and all those "Grimm's Fairy Tales" about wolves adopting human clothes and deceiving people. It's because they are like us. They've got the same sort of social intelligence.

(SOUNDBITE OF WOLF HOWLING)

MONBIOT: And they look at you as if they can read your thoughts. And in fact, to an extent, they can. That's why we domesticated them. That's why dogs are so useful to us because they can read our thoughts. They understand what we want them to do.

RAZ: And what we wanted the wolves to do, to take part in an experiment. An experiment to repopulate Yellowstone National Park. So in 1995, they were quietly reintroduced there. George picks up the story from here in his TED Talk.

(SOUNDBITE OF TED TALK)

MONBIOT: Before the wolves turned up, they'd been absent for 70 years. The numbers of deer, because there were nothing to hunt them, had built up and built up in the Yellowstone Park. And despite efforts by humans to control them, they'd managed to reduce much of the vegetation there to almost nothing. They just grazed it away. But as soon as the wolves arrived, even though they were few in number, they started to have the most remarkable effects. First, of course, they killed some of the deer, but that wasn't the major thing. Much more significantly, they radically changed the behavior of the deer. The deer started avoiding certain parts of the park, the places where they could be trapped most easily, particularly the valleys and the gorges. And immediately, those places started to regenerate. In some areas, the height of the trees quintupled in just six years. Bare valley sides quickly became forests of Aspen and Willow and Cottonwood. And as soon as that happened, the birds started moving in. The number of song birds and migratory birds started to increase greatly.

The number of beavers started to increase because beavers like to eat the trees. And beavers, like wolves, are ecosystem engineers. They create niches for other species and the dams they built in the rivers provided habitats for otters and muskrats and ducks and fish and reptiles and amphibians. The wolves killed coyotes, and as a result of that, the number of rabbits and mice began to rise, which meant more hawks, more weasels, more foxes, more badgers. Ravens and bald eagles came down to feed on the carrion that the wolves had left. Bears fed on it too and their population began to rise as well, partly also, because there were more berries growing on the regenerating shrubs. And the bears reinforced the impact of the wolves by killing some of the calves of the deer.

But here's where it gets really interesting. The wolves changed the behavior of the rivers. They began to meander less. There was less erosion. The channels narrowed. More pools formed. More riffle sections. All of which were great for wildlife habitats. The rivers changed in response to the wolves. And the reason was that the regenerating forests stabilized the banks so that they collapsed less often so that the rivers became more fixed in their course. So the wolves, small in number, transformed not just the ecosystem of the Yellowstone National Park, this huge area of land, but also its physical geography.

Whales in the southern oceans have similarly wide-ranging effects. One of the many post-rational excuses made by the Japanese government for killing whales is that they said, well, the number of fish and krill will rise and then there'll be more for people to eat. Well, it's a stupid excuse, but it sort of kind of makes sense doesn't it because you'd think whales eat huge amounts of fish and krill so obviously take the whales away, there will be more fish and krill. But the opposite happened. You take the whales away and the number of krill collapses. Why would that possibly have happened? Well, it now turns out that the whales are crucial to sustaining that entire ecosystem. And one of the reasons for this is that they often feed at depth and then they come up to the surface and produce what biologists politely call large fecal plumes. Huge explosions of poop right across the surface waters, up in the photic zone where there's enough light to allow photosynthesis to take place. And that - those great plumes of fertilizer stimulate the growth of phytoplankton, the plant plankton at the bottom of the food chain, which stimulate the growth of zooplankton, which feed the fish and the krill and all the rest of it.

And when you look at it like that, you think, wait a minute. Here are the wolves changing the physical geography of the Yellowstone National Park. Here are the whales changing the composition of the atmosphere. You begin to see that, possibly, the evidence supporting James Lovelock's Gaia hypotheses, which conceives of the world as a coherent, self-regulating organism, is beginning, at the ecosystem level, to accumulate. And they make, in my view, a powerful case for the reintroduction of missing species. Rewilding, to me, means bringing back some of the missing plants and animals. It means taking down the fences. It means blocking the drainage ditches. It means preventing commercial fishing in some large areas of sea, but otherwise, stepping back. It lets nature decide. And nature, by and large, is pretty good at deciding.

RAZ: It's interesting 'cause your idea sounds almost primitive, but it requires a great deal of sort of technological know-how and thought, I guess, to make it work, right?

MONBIOT: Yes. It's interesting, this association with primitivism because I actually, I see rewilding as being very much a project about the future. Whereas conservation, in many parts of the world, is about the past, trying to lock in past ecosystems. And rather than with rewilding is to say, let's bring back a lot of exciting keystone species and then stand back and see what happens. But I think it's far from being a primitive project. It's a very modern project. And I think a thrilling one.

RAZ: It's easy for us to forget that, you know, we're just participants in a system, right, rather than the center of it.

MONBIOT: That's right. We have this very anthropocentric world view, but I would like us to be able to show a bit more humility, really, and allow us to make space for nature to create some scope for other species to flourish, rather more than they do at the moment.

RAZ: So George Monbiot doesn't think that we should just do things like put wolves back in Yellowstone or help whales keep control over the oceans.

(SOUNDBITE OF TED TALK)

MONBIOT: Perhaps we should also start thinking about the return of some of our lost megafauna. What megafauna, you say. Well, every continent had one apart from Antarctica. When Trafalgar Square in London was excavated, the river gravels there were found to be stuffed with the bones of hippopotamus, rhinos, elephants, hyenas, lions. Yes, ladies and gentlemen, there were lions in Trafalgar Square long before Nelson's Column was built. All these species lived here in the last interglacial period when temperatures were pretty similar to our own. It's not climate largely which has got rid of the world's megafaunas. It's pressure from the human population - hunting and destroying the habitats - which has done so.

RAZ: But you're not talking about, like, bringing lions back to Britain right?

MONBIOT: It may require a little public persuasion. The climate for the lions reintroduction has so far been muted, but in Europe, there are huge areas, which are now being vacated by farmers. And one estimate suggests that by 2030, we're looking at 30 million hectares, which is an area the size of Poland. And what are we going to do with that land? Well, I say let's create some really big national parks and let's repopulate them with our missing megafauna. Let's bring back the lions. Let's bring back the hyenas and the hippos. And they might also provide some extra protection for species which are under serious trouble in the places where they live at the moment. And maybe this will give them an extra chance of survival.

(SOUNDBITE OF TED TALK)

MONBIOT: Why not reintroduce some of our lost megafauna or at least species closely related to those which have become extinct everywhere? Why shouldn't all of us have a Serengeti on our doorsteps? And perhaps this is the most important thing that rewilding offers us. The most important thing that's missing from our lives - hope. In motivating people to love and defend the natural world, an ounce of hope is worth a ton of despair. The story rewilding tells us is that ecological change need not always proceed in one direction. It offers us a hope that our silent spring can be replaced by a raucous summer. Thank you.

(APPLAUSE)

RAZ: George Monbiot. His book about rewilding is called "Feral" and his entire TED Talk is at TED.NPR.org. Our show today, everything is connected. I'm Guy Raz. More TED Radio Hour in a moment from NPR. Transcript provided by NPR, Copyright NPR.